1. Field of the Invention
Conventionally, there is a component pick up and mounting devices (simply referred to as "mounter" hereinafter) for placing electronic parts (simply referred to as "parts" hereinafter) on a circuit board (simply referred to as a "board" hereinafter). The mounter is classified into two major types. One type is implemented by a number of (for example, 16) operating heads (simply referred to as "heads" hereinafter) which circulate, rotate, pick up and place parts. This type is generally called a rotary type. The other is implemented by one or a plurality of heads (normally 2 to 7) arranged on one move support, which pick up and place parts on a board while moving forward and backward, to the right and to the left, and upward and downward. This type is normally called a one-by-one type.
2. Description of the Related Arts
To efficiently place parts on a board with the above described one-by-one type mounter, the amount of movement of a head must be reduced to a minimum. Upward and downward movements for mounting among the movements of the head are intended to pick up and place parts, and essentially arise. Also the forward and backward (in the direction of the Y axis) movements of the head for placing parts are movements between a part supply device and a board placing position, and essentially arise. Since these movements are also essential, it is difficult to reduce the amounts of the movements.
In the meantime, the amounts of movements of a plurality of heads to the left and right (in the direction of the X axis) for picking up parts are affected depending on the positions of parts to be supplied to a head. Additionally, the positions of the parts exactly match the head pitches of the plurality of heads, they can be simultaneously picked up and the amounts of the upward and downward movements of the heads can be reduced. Therefore, supply devices such as a part cassette, a part stick, a part tray etc., are arranged at the optimum positions, so that the amounts of movements to the left and right and also movements of the upward and downward by the plurality of heads must be reduced to a minimum. At the same time, parts must be simultaneously picked up as much as possible. To optimally set the positions of the supply devices, the pick up combination of parts, which allows a plurality of heads to pick up the parts efficiently, must first be determined.
The operations for determining the pick up combination of parts is implemented as follows. That is, all possible combinations of parts to be picked up by nozzles of a plurality of heads are first considered. Then, a combination which seems to be optimum is selected by examining which combination can perform the pick up operations in the shortest time. Supply devices are arranged according to the selected combination so that parts can be picked up. The selected and determined pick up combination of parts must be included into a part mounting program for use in a mounter.
For the above described selection and determination of the pick up combination of parts, actual parts are assigned to possible combinations of parts, and their pick up operations are estimated. Then, a combination which seems to be faster is repeatedly selected. The operations for optimally making a pick up combination of parts were performed manually and were extremely troublesome and complicated. This is because they were performed by trial and error. Since the operations for considering (searching for) a pick up combination of parts were troublesome and time consuming, they impeded improvement of operating efficiency of an entire process in which a new board was designed, a pick up combination of parts was finally determined based on the design of the board, supply devices were arranged based on the determined combination, and a new mounting process was ready to start up on a production line. The present invention was developed so as to overcome such a problem where the improvement of the operating efficiency is impeded. It aims at providing a parameter generating device for a part mounting program, which automatically makes an optimum combination that can efficiently pick up parts to be placed.